Conventionally, a slip ring device having a mechanical contact is used when a power source line is connected to load equipment or the like via a structural rotary member.
This slip ring device is comprised of a ring-shaped slip ring to which a transmission power supply is connected and which is arranged on the outer surface of the rotary member via an insulator, and a brush to which a reception power supply is connected and which is in sliding contact with to the outer surface of a slip ring. Load equipment or the like is connected to the reception power supply. With this configuration, the slip ring and the brush are electrically connected to each other, and the electric power can be transmitted from the transmission power supply to the reception power supply. In addition, by providing multiple pairs each having the slip ring and the brush in that slip ring device, multiplexing of a plurality of electric power can be carried out.